Asymmetrical ureas and their production



Patented Dec. 3, 1935 UNITED STATE-S PATENT OFFICE- ASYMM'ETRICAL UREAS AND THEIR PRODUCTION Josef Hilger, Cologne-Mulheim, and Carl Taube,

Leverkusen-Wiesdorf,

Germany, assignors to General Aniline Works, Inc., New York, N. Y., a corporation of Delaware No Drawing. Application March 16, 1932, Serial No. 599,344. In Germany'March 19, 1931 8 Claims.

an alkoxy group, the nitro group or an esterified carboxylic acid group, and X stands for hydrogen or alkyl and Y stands for radicals of the benzene or naphthalene series.

Our new products are obtainable by causing an isocyanate of an aminoazo-compound free from a free carboxylic acid or a free sulfonic acid group and ammonia or a primary or secondary amine of the aliphatic, aromatic or aliphaticaromatic series, to act upon each other in a 25 solvent.

The process is favorably carried out by Working with about molecular quantities of the two reacting components; the temperatures required 30 used, but as a general rule it may be stated that tween about 30 C. and about 100 C. In this connection it is to be said that due to the evolution 35 some cases the process can be performed without heating.

In case both components are freefrom a free sulfonic or carboxylic acid group, there are ad 40 vents, such as benzene, chlorobenzene, nitrobentemperatures, the final temperature not exceed- 55 ing 100 C. These azo isocyanates and the process of their manufacture have been described in U. S. Patent 1,916,314.

The amino isocyanates coming into consideration for the purpose of our invention hereafter are illustrated by the formula of some types.

noanthraquinone, etc., alkylarylamines, such as wherein R, X and Y amine, N-ethyl-naphthylamine, or their substitution products, e. g. alkyl-, halogen-, hydroxy-, alkoxy-derivatives or sulfoni c acids or carboxylic acids thereof.

The process of our invention proceeds according to the following equation:

are to be defined as stated above.

()ur new products are, when free from'a free sulfonic or carboxylic acid well crystallizing, yelsulting urea separates after a short time. it'has the'formula l I C1 CH3 and crystallizes from benzine in the shape of reddish brown needles melting at 204 C. On starting from the isocyanate from the saponified aminoazo compound obtained from diazotized l-aminoacetanilide and 1-phenyl-3-methyl-5- pyrazolone, a urea is obtained in the form of leaflets melting at 235 C. having the formula low to brownish organic solvents,

, SOaNa- SOaNa is precipitated with the aid of common salt, fil

tered 01f and dried. The urea is in the form of its sodium salt soluble in water with a yellow coloration; by the addition of an acid a reddish-brown precipitate is obtained.

Similar products are obtained on starting e. g. from the 4(4-methoxyphenylazo) 3 -methylphenyl-isocyanate of the formula or from the isocyanate of the formula V 7 CH V V 7 Instead of the 1,8-aminonaphthol-3,6-disulfonic acid other amino-naphthol sulfonic acids can be used, e. g. the 1,8-aminonaphthol-4,6-dior -6-monosulfonic acid, the 2,5-aminonaphthol-7 sulfonic acid, the 2,8-aminonaphthol-6-sulfonic acid, or aminonaphthalene-sulfonic acids etc.

Example 2.--To a benzene solution of 301 parts of the isocyanate of the aminoazo compound from diazotized Z-chloroaniline and 3-amino-4-cresolmethylether 93 parts of aniline are added and heated for one hour on the water-bath. The rethemselves or are valuable are soluble with alcohol, easily soluble in glacial acetic acid and in a consisting of ammonia,

CH The aniline can be replaced by other amines, e. g. by naphthylamines, toluidines, chloroaniline, nitrcanilines, aminophenols, anisidines and aminoazocompounds.

Example 3.-3l.9 parts of the isocyanate of i-aminophenyl-L-azo-1-phenyl-3- methyl 5 pyrazolone of the formula are dissolved in benzene and are heated on the water bath for one hour to 60 C. with 50 parts of concentrated ammonia whilst stirring. The precipitated dye is filtered with suction and crystallized from alcohol. It separates in the shape of yellow crystals melting at 258 C. They difficulty in benzene and cold hot spirit.

Example 4.223 parts of the isocyanate prepared fromA-amino-azobenzene are heated while a stirring with 107 parts of monomethylaniline for about hour in an oil bath having a temperature of 140 C. After cooling, the solidified mass is dissolved in benzene and filtered; from the filtrate the urea of the formula V V CE;

I g H 0.115

crystallizes. 1

We claim:

1. The process which comprises causing an isocyanate of an aminoazo-compoundfree'from a free sulfonic or carboxylic' acid group to act upon a compound of the'group consisting of ammonia, primary amines of the aliphatic. or aromatic series and secondary amines of the allphatic, aromatic and aliphatic-aromatic series in a solvent at a temperature'between about 30 and about 100 C. V

. 2. The process which comprises causing an isocyanate of an aminoazo-compound which may be substituted in the nuclei by substituents selected from the group consisting of alkyl, hydroxyalkyl, halogen, the hydroxy group,

an alkoxy group, the nitro group or an esterified carboxylic acid group, to act upon a compound of the group primary amines of the aliphatic or aromatic series and secondary amines of the aliphatic, aromatic and aliphatic-aromatic series in a solvent at a temperature between about 30 and about 100 C.

3. The process which comprises causing an isocyanate of the general formula:

wherein R and R stand for radicals of the benzene or naphthalene series which may be substituted by substituents selected from the group consisting of alkyl, hydroxyalkyl, halogen, the hydroxy group, an alkoxy group, the nitro group or an esterified carboxylic acid group, to act upon aminonaphthol-sulfonic acid in aqueous solution at a temperature between about 30 and about 100 C.

5. The process which comprises causing about molecular proportions of phenylazophenyl-isocyanate and 1,8-aminonaphthol-3,G-disulfonic acid to act upon each other in a neutral aqueous medium.

6. Asymmetrical ureas of the general formula:

wherein R stands for the radical of an aminoazocompound free from a free carboxylic acid or a free sulfonic acid group, X stands for hydrogen or alkyl and Y stands for an amino-naphtholsulfonic acid radical, forming well crystallizing, yellow to brown substances and being valuable intermediate products for the manufacture of dyestuffs.

7. Asymmetrical ureas of the general formula:

stand for radicals of the benzene or naphthalene series which may be substituted by substituents selected from the group consisting of alkyl, hydroxyalkyl, halogen, the hydroxy group, an alkoxy group, the nitro group or an esterified carboxylic acid group, Xstands for hydrogen or alkyl and Y stands for an aminonaphthol-sulfonic acid radical, forming well crystallizing, yellow to brown substances and being valuable intermediate products for the manufacture of dyestuffs.

8. The urea of the following formula:

being a well crystallizing, reddish-brown substance and being a valuable intermediate product for the manufacture of dyestuffs.

JOSEF HILGER. CARL TAUBE. 

